Modern computing systems can support a variety of intercommunication protocols. In certain instances, computers can connect with each other using one network protocol, while appearing to outside users to use another network protocol. Commonly termed an “overlay” network, such computer networks are effectively built on the top of another computer network, with nodes in the overlay network being connected by virtual or logical links to the underlying network. For example, some types of distributed cloud systems, peer-to-peer networks and client-server applications can be considered to be overlay networks that run on top of conventional Internet TCP/IP protocols. Overlay networks are of particular use when a virtual local network must be provided using multiple intermediate physical networks that separate the multiple computing nodes. The overlay network may be built by encapsulating communications and embedding virtual network address information for a virtual network in a larger physical network address space used for a networking protocol of the one or more intermediate physical networks.
Overlay networks are particularly useful for environments where different physical network servers, processors, and storage units are used, and network addresses to such devices may commonly change. An outside user would ordinarily prefer to communicate with a particular computing device using a constant address or link, even when the actual device might have a frequently changing address. However, overlay networks do require additional computational processing power to run, so efficient network translation mechanisms are necessary, particularly when large numbers of network transactions occur.